Question

Instead of supporting method overloading Ruby overwrites existing methods. Can anyone explain why the language was designed this way?

Answer 1

Method overloading can be achieved by declaring two methods with the same name and different signatures. These different signatures can be either,

1. Arguments with different data types, eg: method(int a, int b) vs method(String a, String b)
2. Variable number of arguments, eg: method(a) vs method(a, b)

We cannot achieve method overloading using the first way because there is no data type declaration in ruby(dynamic typed language). So the only way to define the above method is def(a,b)

With the second option, it might look like we can achieve method overloading, but we can’t. Let say I have two methods with different number of arguments,

def method(a); end;
def method(a, b = true); end; # second argument has a default value

method(10)
# Now the method call can match the first one as well as the second one, 
# so here is the problem.

So ruby needs to maintain one method in the method look up chain with a unique name.